I really hate my phone (marbl). I honestly don't like any of virgin mobile phones, although i love their plan. I love tmobile and sprint phones.
No, you can only use Virgin Mobile phones on Virgin Mobile. I've tried to put other phones on it but they never let me. I hate their phones too. Maybe you should just go with a pre paid with another provider, like T-Mobile flex pay. It's pretty much pre paid, but you have to pay full retail price for the phone, but it's worth it. :) Or ATT Go Phone. I don't know how that works really since I went with the Flex Pay, but either way you'd be getting a much better phone. :)